While you are not required to purchase insurance from the rental company, it might be a good idea to do so. Insurance can cover car damage or injury, in the event that you are involved in an accident.
If you have auto insurance already, you may not need to pay for additional coverage from the rental company. Most personal insurance policies cover rental cars, as well. However, check your policy or call the company to confirm and to determine if there are any limits or exceptions – for instance, renting certain types of vehicles or renting for extended periods of time. You may also want to fill in any gaps in your personal insurance with rental insurance.